Monitoring method of productivity of natural grassland in Sichuan Province

The productivity of natural grassland in Sichuan Province during the period 2006-2009 was estimated by combing the field survey and remote sensing monitoring methods.This study used the vegetation index(EVI) to establish the estimation model for predicting the yield of main grassland types by many times modification and verification.This estimation model was used to assess the grassland production during 2007-2009 in Sichuan Province,and indicating that the averaged unit yield of grassland was 4 752 kg/ha,the total palatable fresh forage yield was 8.39×1010 kg(equivalent to 2.53×1010 kg hay yield),and the theoretical stocking rate was 29.69×106 sheep unit.This study further showed that the estimation yield from model was in accord to those from field survey in each region,and suggested that this model could be applied to grassland yield estimation in the large range scale in Sichuan Province.